解,1/a+1/b+1/c =(a+b+c)/a+(a+b+c)/b+1(a+b+c)/c =1+b/a+c/a+1+a/b+c/b+1+a/c+b/c ≥3+2√(b/axa/b)+2√(c/axa/c)+2√c/bxb/c =9芸共.其中a=b=c=1/3 分析1=a+b+c,由想做尖子生去了解 全权方和不等式
